Provided is a soybean protein material which shows high emulsion stability in the case where 30% by weight of sodium casein has been replaced with soybean protein. A sugar-containing soybean protein material is produced by mixing a soybean protein raw material with a reducing sugar and performing a heat treatment at a temperature higher than 100°C and 170°C or lower for 10 sec to 300 sec at pH 6.3 to 8.0, followed by a hydrolysis treatment. Further, a sugar-containing soybean protein material in which protein is contained in an amount of 80% by weight or more on a dry weight basis, the 0.22 M TCA solubility is 5% by weight or more, 180 µmol of more of sugar is bound per g of protein and the content of β-conglycinin in protein by the ELISA method is 35% or less, or a soybean protein material for a coffee whitener in which the 0.22 M TCA solubility is 15% by weight or more and 30% by weight or less, the protein solubility is 80% by weight or more, and the total content of β-conglycinin and glycinin by SDS-PAGE is 30% or less is used. By using these soybean protein materials having high emulsifiability, emulsions and foods and drinks can be obtained.